Bamboo Server is a CI/CD solution which is part of the Atlassian suite of developer tools. It is available only in a self-managed configuration and is a closed source solution. Bamboo offers build, test, and deployment automation, and has tight integrations to Atlassian Bitbucket (for SCM) and Fisheye (for understanding how source code has changed), as well as integrations to over 150 other tools. In contrast, GitLab offers a git-based SCM, SCM integrations, and code change traceability out of the box in a single application.
Bamboo offers a GUI for defining build plans, and offers pipeline as code through Java and Yaml. Bamboo also offers deployment plans (which include the notion of environments and releases), pre-deployment visibility, and per-environment deployment permissions. GitLab also offers release tracking across environments and deep visibility into the changes in a deployment, but sets deployment permissions based on branch permissions.
Bamboo does not offer monitoring. GitLab includes monitoring as part of its single application.
Bamboo steps can be run in parallel across agents, and those agents can be auto-scaled based on need if Bamboo is configured for a feature called Elastic Bamboo. Elastic Bamboo requires the use of "remote agents", which you pay extra for (see pricing). Organizations who want auto-scaling are also locked in to using Amazon Elastic Compute Cloud (EC2) and paying Amazon separately for their usage. In contrast, GitLab does not charge per remote agent (runner) and scales with a variety of cloud and container solutions.
"we have also started using GitLab (moving from our own Bitbucket/Bamboo servers). The CI/CD is definitely an improvement but I'm not sold on the code review features of GitLab"
"Sweet. Unlike Atlassian's Bamboo, @GitLab CI supports "[ci skip]" out of the box. #gitlab #devtools #success"
"Nice and simple GUI in @GitLab CI as well. Much easier to navigate than Bamboo for instance. #gitlab #gui #ux #success"
"Seriously, is still there a reason to use Jenkins/Hudson/TeamCity/Bamboo? I reckon @GitLab built-in CI support is sufficient for most of us!"
"A day building pipelines in VSTS for one of my teams. Get the feeling that while I find it simple not everyone finds it the same. Better than Gitlab CI (IMO) but I like Bamboo a lot too…"
From Bamboo open Issues